*{
  margin: 0;
  padding: 0;
  box-sizing: border-box;
  //tap高亮
  -webkit-tap-highlight-color: transparent;
}
ul,ol{
  list-style: none;
}
a{
  text-decoration: none;
}
.fl{
  float: left;
}
.fr{
  float: right;
}
.clearfix::before,
.clearfix::after{
  content: '';
  display: block;
  line-height: 0;
  height: 0;
  clear: both;
  visibility: hidden;
 }
 .clearfix{
   //移动端这里省略
   zoom: 1;
 }
 //计算尺寸函数
@function p2r($size){
  @return ($size/54)*1rem;
}
//设置图片居中  background center
@mixin bgc ($url,$width){
  background: url($url) no-repeat center / 100% 100%;
  position: absolute;
  left: 50%;
  margin-left: p2r(-$width/2);
}
//设置元素水平居中
@mixin lc ($width){
  left: 50%;
  margin-left: p2r(-$width/2);
}
//设置元素垂直居中
@mixin vc ($width){
  top: 50%;
  margin-top:p2r(-$width/2);
}
//直接设置背景图 不考虑居中
@mixin bg ($url,$width){
  background: url($url) no-repeat center / 100% 100%;
  position: absolute;
}
//设置尺寸
@mixin size ($width,$height){
  width: p2r($width);
  height: p2r($height);
}

